Yumi Shimura was a Japanese voice actor born on November 30, 1982, in Yamanashi Prefecture. Before entering the entertainment industry, she worked as an office clerk. She pursued her interest in voice acting by studying at the Japan Narration Acting Institute while continuing to work, which eventually led to her joining the talent agency I'm Enterprise.

Shimura made her debut as a voice actor in 2004 or 2005 with her first major role as Chisame Hasegawa in the anime and related adaptations of Mahō Sensei Negima, a part she would reprise across multiple series, OVAs, and games throughout her career. Her performance as Chisame Hasegawa became one of her signature roles, and she also contributed to several theme song performances for the Negima! anime.

Another defining role for Shimura was Kanaria in the Rozen Maiden franchise. She voiced the character in Rozen Maiden: Träumend, Rozen Maiden: Ouvertüre, and later in the 2013 series Rozen Maiden: Zurückspulen. In video games, she was known for voicing Cocona Bartel in the Ar tonelico series and Saki Tsuzura in the Arcana Heart fighting game series. Her other notable anime roles included Asami Minakawa in Mushi-Uta, Wakaba Ogino in Cuticle Detective Inaba, and the Goddess of Iron Wall Lucie in Tanken Driland - 1000-nen no Mahō. She also had minor roles in series such as Clannad and Sgt. Frog.

Shimura was notably the shortest voice actor in the Japanese industry at the time, with a height of 138.8 centimeters. This physical characteristic reportedly led to her using her own small stepladder in the recording studio and having a dedicated low-positioned microphone installed for her convenience.

On June 30, 2016, Shimura announced on her personal blog that she was retiring from the voice acting industry and leaving her agency, I'm Enterprise. In her farewell message, she expressed her gratitude for the enjoyable experiences and the kindness she received from colleagues and fans throughout her career.